A fiber-reinforced composite material in which carbon fibers, aramid fibers, glass fibers or the like are used as reinforcing fibers has been widely utilized for structural materials of aircrafts, vehicles or the like, or in general industries and sports such as a tennis racket, a golf club shaft and a fishing rod by utilizing high specific strength and high specific elasticity thereof.
In molding a shaped product constituted by the fiber-reinforced composite material, it has been proposed that base materials including discontinuous reinforcing fibers and a resin are layered to prepare a preform, the preform is arranged in a wider range than a total mold cavity area, and the perform is press-molded. See Japanese Patent Laid-Open Publication No. 2010-253938.
However, in this molding method, the outer periphery portion of the shaped product is required to be trimmed. For this reason, a large amount of offcuts are produced, and the disposal thereof incurs costs. In order to obtain an integrated shaped product that substantially exhibits isotropy, it must be careful to ensure that symmetrically layering is always made, and thus the discretion degree of the time for preparing perform and the arrangement method in molding is low.
Also, a method of obtaining a shaped product constituted by a fiber-reinforced composite by molding a composition including reinforcing fibers and a resin through injection molding is performed. See Japanese Patent Laid-Open Publication H04-193504. However, this method employs so-called long fiber composite pellets, in which an average length of the reinforcing fibers ranges from about 5 mm to 15 mm, and the length of the reinforcing fibers is largely reduced in the shaped product after the injection molding.